ICQ 7

ICQ was the first instant messenger client available - pioneered by Mirabilis in 1996. For many years ICQ was the most popular client on the market, but lately it has been surpassed by MSN Messenger, AOL Instant Messenger (AIM) and others.
However, ICQ still has many advanced features and has been the first to introduce a number of cutting edge functionalities - such as sending SMSes. Apart from standard chat ICQ also supports video and voice (VoIP) chat. Skinning is also an important part of ICQ allowing people to change the look and feel for their ICQ client. ICQ is available in virtually any language.

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